Combination and Assessment of GNSS Clock Products from iGMAS Analysis Centers

doi:10.11947/j.AGCS.2016.F025

Abstract

Abstract:

The precise clock corrections are a prerequisite for applications of the GNSS positioning, navigation and timing (PNT) service. Therefore the combination and assessment for clock products is one of the important tasks of product integration and service center (ISC). First of all, it is introduced that the improved strategy and robust estimation of clock combination. The issues including nonlinear systematic error processing, alignment of clock reference and compensation of linear systematic error are highlighted. Furthermore, two combined products using epoch-wise clock alignment and the "three-step" alignment respectively are compared, and the clock products of recent two years from iGMAS are analyzed and evaluated in detail. Finally, in order to verify the accuracy and consistency of the combined products, PPP tests are implemented using static data from 5 IGS stations. The results show that the clock RMS of combined solutions is the best, which can be used as reference to assess the clock quality of analysis centers (ACs). The results of BDS only static PPP using the final combined products is within 4 cm, which is better than that of most ACs.

Key words: iGMAS, multi-GNSS, clock combination, systematic error, Robust estimation

CLC Number:

P228

CHEN Kangkang, XU Tianhe, YANG Yuguo, CAI Hongliang, CHEN Guo. Combination and Assessment of GNSS Clock Products from iGMAS Analysis Centers[J]. Acta Geodaetica et Cartographica Sinica, 2016, 45(S2): 46-53.

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